A uniform object of mass, m1, sits at rest on a slope inclined at 45 o to the horizontal. The object is held in place by the tension in a rope which passes over a frictionless pulley and is attached to a free-hanging mass, m2.
The mass of m2 is 1kg. The mass of m1 is unknown.
If the angle of the slope is increased to 60 o then m1 will begin to slide down the slope. When the angle of the slope is decreased to 30 o then m1 will start to move up the slope.
The magnitude of friction F is given by F = μR where R is the normal reaction force and μ is a constant called the coefficient of friction.
Which line, A to D, in the table below, gives the value of m1 and the value of μ?
| Mass / kg | μ |
A | 0.73 | -1.01 |
B | 1.37 | 0.27 |
C | 1.37 | -0.27 |
D | 0.73 | 1.01 |